Electrical properties and temperature stability of a new kind of lead-free piezoelectric ceramics

Abstract

0.995[(K0.50Na0.50)0.94Li0.06]NbO3–0.005AETiO3 (AE=Ca, Sr, Mg, Ba) lead-free piezoelectric ceramics were prepared by normal sintering. The effects of the AETiO3 and poling temperature on the electrical properties of the ceramics were carefully studied, and the temperature stability of the electrical properties of the ceramics was also investigated. The experimental results show that the ceramics with Li and CaTiO3 possess the pure phase, Li and AETiO3improves the electrical properties of the pure (K0.50Na0.50)NbO3 ceramics, the poling temperature near tetragonal and orthorhombic phase transition will enhance the piezoelectric properties of the ceramics and the KNLN–CT ceramics exhibit good temperature stability of electrical properties for tetragonal and orthorhombic phase transition below room temperature. The KNLN–CT ceramics exhibit relatively good properties: d33 = 172 pC N−1, kp = 0.43, tan δ = 0.032, εr = 771 and Tc = 465 °C. As a result, the KNLN–CT ceramic is promising candidate material for piezoelectric devices.